title: Device related complications of the Coflex interspinous process implant for the lumbar spine.
abstract: BACKGROUND
  Coflex, a type of interspinous process implant, can provide intervertebral dynamic stability for surgical segments and effectively relieve lumbocrural pain. However, few studies have described therapeutic strategies and the avoidance of Coflex implant complications.
  
  
  METHODS
  Coflex implant complications in this study included intraoperative or postoperative spinous process fracture, aggravated postoperative lumbocrural pain, dislodgment and malposition. The complications were analyzed, and therapeutic strategies were applied according to the specific complication. The Visual Analogue Scale and Oswestry Disability Index scores were evaluated by using the paired-samples test from SPSS 12.0.
  
  
  RESULTS
  Conservative treatment was provided to seven patients who experienced aggravated lumbocrural pain even though their devices remained in the correct position, and pedicle screw treatment was used as an alternative in four cases. The Visual Analogue Scale and Oswestry Disability Index scores showed evident improvement in these patients. The Visual Analogue Scale and Oswestry Disability Index scores of two patients who underwent revision were also improved.
  
  
  CONCLUSIONS
  Coflex implants should be avoided in patients with osteoporosis, a narrow interspinous space and intervertebral coronal spondylolysis, or sagittal instability. Furthermore the device choice, depth of implantation, and clamping intensity should be appropriate. Conservative treatment can be provided to patients with symptoms if the device remains in the correct position; however, revisions and salvages should be undertaken with internal fixation of pedicle screws for patients with device malposition, intraoperative implantation failure, or device intolerance.
authors.affiliation: Department of Orthopedics, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zang
authors.forename: Peng
authors.initials: P
authors.lastname: DU
authors.forename: Yong
authors.initials: Y
authors.lastname: Hai
authors.forename: Qing-jun
authors.initials: QJ
authors.lastname: Su
authors.forename: Shi-bao
authors.initials: SB
authors.lastname: Lu
authors.forename: Tie
authors.initials: T
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001863:Bone Screws; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019736:Prostheses and Implants / Q000009:adverse effects*; D064232:Visual Analog Scale